Older but good
article about general kidnapping/abduction facts. From other things I've read, these still hold pretty true. The paragraph that I found most applies to Jayme's case is:
Reading through it, the scenario which has the most characteristic matches as Jayme's case is:
involves a comparatively high percentage of juvenile perpetrators, has the largest percentage of female and teenage victims, is more often associated with other crimes (especially sexual and physical assault), occurs at homes and residences, and has the highest percentage of injured victims. When acquaintance kidnappings end in murder, the murder happens quickly. According to a study by the Washington State Attorney General's Office, in 74 percent of missing-child homicides, the child is murdered within the first three hours of the abduction.
Aside from the last sentence giving me chills
, unless this is a home invasion gone wrong, which still seems less likely, the known facts support that either Jayme knew her abductor, her abductor knew her or both. Still would be extremely surprised if this was a totally random robbery gone wrong.